Eyebrows help keep moisture out of our eyes when we sweat or walk around in the rain. The arch shape diverts the rain or sweat around to the sides of our face, keeping our eyes relatively dry. The most obvious advantage of this is that it lets us see clearly when we're sweating a lot or out in the rain. Without eyebrows, getting around in these conditions is a little more difficult. The shape of your brow itself diverts a certain amount of moisture, but eyebrows make a significant difference in your ability to see. Diverting the sweat away is also good because the salt in sweat irritates the eyes, making them sting a little.
Most scientists are inclined to believe that if we didn't have eyebrows, something else would have evolved to help the situation. For example, humans could have developed incredibly thick eyelashes to shield out excess sweat or rain. Or, our skulls could have continued to protrude so that they formed a ledge above our eyes. Rain or sweat would then drop from that ledge straight away from our faces, without going in our eyes.
Matt: CORRECT
Record: 58-36
No comments:
Post a Comment